Desktop.DASH PLC Setup
November 2012
The first step was to choose a communications driver and configure some basic settings.
Home Desktop.DASH
Next we need to configure the target device, by choosing Main Menu > System > Connected PLC.
Connected PLC Menu Item
Connected PLC Dialogue
How the above dialogue looks and operates is dependent upon the selected driver, as shown in the bottom left hand side of the form.
(Note: If your required driver is not the one displayed, then you really need to read the instructions on the previous page:- Desktop.DASH)
Ethernet Device Configuration
If we're using "MC Protocol" - then the hardware is a FX3GE, a FX3G + ENET, or a FX5U with SLMP configured.
For the FX3GE - configure MC Protocol under the PLC Parameters > Ethernet Port settings.
For FX3G + ENET this must be configured in the target ENET module using the Mitsubishi programming tool FX-Configurator-EN.
Also, the target ENET type module MUST be on the same sub-net as the host PC which is running Desktop.DASH, and of course the listening Port Number must be set as required too.
This might help... FX ENET Setup Example Reference
And for FX5U - configure SLMP under the FX5UCPU > Ethernet Port > External Device Configuration settings.
Before using the [Test Connection] button, you should verify that you can actually PING the device first using a Command Prompt in Windows.
The Read Delay (ms) value is critical for the type of device you are communicating with, and it's used to define how much time the app should wait after sending a command to a device before checking for a response. For Ethernet 10 ms for a locally connected device is normally fine, for an Alpha2 on the other end of 500 meters of cable connected via a Ethernet to Serial device server 400 ms would be normal.
Press the button to test your settings. A good result will yield as follows...
Ethernet Test OK
Once you have a connection you can do a quick read of DataPoints within the PLC.
From the pull down list choose the required device type, then choose a Start device store and a Range of devices to read. For example, D0 and 8 stores...
MC Protocol Read Range
Press [Read] to get the raw data, for example...
Reading a Range of D Stores
You can also write single stores one at a time. If you know the exact target store then punch it straight in, if however you want to browse for one, then press the [Point...] button...
Device Selector Pop Up
Once a device is selected enter an appropriate value to write, for example:-
1 or 0 for Bit stores, 32767 to -32768 for Word stores and 2147483647 to -2147483648 for Double Word stores
Important Note
To read a double D store you must specify W (this is a homemade nomenclature that doesn't quite align with Mitsubishi device naming conventions!) Where W0 will return D0 + D1 as a double word or 32 Bit value. (Not to be confused with W Stores in L and Q Series!)
Finally, press the [Write] button.
FX Over Serial (RS-232 Configuration)
Desktop.DASH works best with FX over Ethernet installations, however, limited support for legacy FX over Serial connections are provided for.
The FX Serial driver only supports X, Y, M & D stores.
The embedded PDF document below details a typical setup procedure.
Alpha2 Device Configuration
For Alpha2 you will get a different presentation of the dialogue...
Connected PLC - Alpha2
Importantly, the Port # value is now the literal COM Port number. e.g. COM1, COM3 or COM10 on your host PC.
The Alpha2 Station Number MUST be configured as 0 using the MItsubishi AL-VLS programming tool, and the Serial Communications must be set as 9600, 8, N, 1.
The Alpha2 driver only supports reading AI, DI, DO, CB and CW 1 through 8.
In order to read CB or CW stored, either group must be configured in the Alpha2 using the "Dedicated Protocol" feature AND all 8 stores must be established.
Additionally you also have the option to directly scale the Analogue Inputs of the Alpha2 to your real world engineering units to suit the various sensors that can be attached to the 0-10V inputs.
Press [Analogue Scaling] to pop the scaling dialogue...
Scale Alpha2 Analogue Inputs
For an example. A space temperature transmitter with a range of -10 to 40 Deg C over 0-10V could be connected to AI1. The re-scaling feature can then be used to over-ride the default scale of 0-550 Bits to produce the desired direct reading in real world units. Subsequently, when we add a Display object to the dashboard we can introduce a formatting rule like #.# which will convert 215 to 21.5 representing 21.5 Deg C.
To reflect the scaling when you do a quick read you must check [ ] Use In Feedback.
Again, you can write suitable values to CB (Bit) and CW (Word) stores once a license has been installed.
The Analogue Scaling Anomaly
As an aside, you may have wondered why the default HiDef is 500, and not 550 - as reflected in the Mitsubishi ALVLS software. Here is the reason. The Alpha ADC (Analogue to Digital Converter) is 9 Bits or has a step resolution of 512. The ALVLS input simulator, and in fact, even the Serial response from polling an Alpha by software, with for example Desktop.DASH, returns a value between 0 and 550. This is an error. The maximum value obtained can never be more than 512. And in real world practice, only 500 yields an accurate full scale tracking of a 0-10V DC signal applied to the Alpha Analogue Inputs.